Han Meisheng, Mu Yongbiao, Guo Jincong, Wei Lei, Zeng Lin, Zhao Tianshou
Shenzhen Key Laboratory of Advanced Energy Storage, Department of Mechanical and Energy Engineering, SUSTech Energy Institute for Carbon Neutrality, Southern University of Science and Technology, Shenzhen, 518055, People's Republic of China.
Nanomicro Lett. 2023 Mar 31;15(1):80. doi: 10.1007/s40820-023-01042-4.
In-situ construction of electrostatic repulsion between MoS interlayers is first proposed to successfully prepare Co-doped monolayer MoS under high vapor pressure. The doped Co atoms radically decrease bandgap and lithium ion diffusion energy barrier of monolayer MoS and can be transformed into ultrasmall Co nanoparticles (~2 nm) to induce strong surface-capacitance effect during conversion reaction. The Co doped monolayer MoS shows ultrafast ion transport capability along with ultrahigh capacity and outstanding cycling stability as lithium-ion-battery anodes.
High theoretical capacity and unique layered structures make MoS a promising lithium-ion battery anode material. However, the anisotropic ion transport in layered structures and the poor intrinsic conductivity of MoS lead to unacceptable ion transport capability. Here, we propose in-situ construction of interlayer electrostatic repulsion caused by Co+ substituting Mo between MoS layers, which can break the limitation of interlayer van der Waals forces to fabricate monolayer MoS, thus establishing isotropic ion transport paths. Simultaneously, the doped Co atoms change the electronic structure of monolayer MoS, thus improving its intrinsic conductivity. Importantly, the doped Co atoms can be converted into Co nanoparticles to create a space charge region to accelerate ion transport. Hence, the Co-doped monolayer MoS shows ultrafast lithium ion transport capability in half/full cells. This work presents a novel route for the preparation of monolayer MoS and demonstrates its potential for application in fast-charging lithium-ion batteries. [Image: see text]
The online version contains supplementary material available at 10.1007/s40820-023-01042-4.
首次提出在高蒸气压下原位构建二硫化钼（MoS）层间的静电排斥力，成功制备出钴掺杂的单层二硫化钼。掺杂的钴原子极大地降低了单层二硫化钼的带隙和锂离子扩散能垒，并且在转化反应过程中可转变为超小的钴纳米颗粒（约2纳米）以诱导强表面电容效应。钴掺杂的单层二硫化钼作为锂离子电池负极表现出超快的离子传输能力、超高容量和出色的循环稳定性。
高理论容量和独特的层状结构使二硫化钼成为一种有前景的锂离子电池负极材料。然而，层状结构中各向异性的离子传输以及二硫化钼较差的本征电导率导致其离子传输能力无法接受。在此，我们提出通过钴离子（Co+）在二硫化钼层间替代钼来原位构建层间静电排斥力，这可以打破层间范德华力的限制来制备单层二硫化钼，从而建立各向同性的离子传输路径。同时，掺杂的钴原子改变了单层二硫化钼的电子结构，从而提高其本征电导率。重要的是，掺杂的钴原子可转变为钴纳米颗粒以形成空间电荷区来加速离子传输。因此，钴掺杂的单层二硫化钼在半电池/全电池中表现出超快的锂离子传输能力。这项工作为单层二硫化钼的制备提供了一条新途径，并展示了其在快速充电锂离子电池中的应用潜力。[图片：见正文]
网络版包含可在10.1007/s40820-023-01042-4获取的补充材料。
